Fluid pressure control braking mechanism



Oct. 20, 1936. v SHELOR 2,057,796

FLUID PRESSURE CONTROL BRAKING MECHANISM Original Fil ed May 15, 193:5

Patented Oct. 20, 1936 I UNITED STATES PATENT-OFFICE I FLUID PRESSUZZZQIZIE EOI.

MEG

Frederick L. Shelor, Richmond, Va., assignor to Innovation Brakes, Inc.,

Duration of Virginia Richmond, Va., a cor- 8 Claims.

The invention relates-to new ,and useful improvements in a braking mechanism for a motor vehicle. In my co-pending applications Serial Nos. 572,705, filed November 2, 1931, now Patent No. 1,948,190, issued February 20, 1934 and 652,389, filed January 18, 1933, there is shown and described a braking mechanism for the wheels of a motor vehicle wherein spaced disks, one of which is non-rotating, are movable relative to each other in a direction axially of the wheel for bringing the brake shoes into contact with the braking member carried by and moving with the wheel. These disks are connected by flexible members so 'as to form therebetween a vacuum chamber.

An object of the present invention is to provide a braking mechanism of the above type wherein the space which must be put under vacuum is reduced to a minimum without reducing the effective area of atmospheric pressure operating to move the disks relative to each other and apply the brake shoes to the braking member.

A further object of the invention is to provide a braking mechanism wherein the disks are connected by resilient members forming a closed vacuum chamber between the disks, permitting said disks to move relative to each other and operating to force the disks apart when the chamber therebetween is at atmospheric pressure.

A still further object of the invention is to provide a braking mechanism of the above type wherein one of the brake shoes is mounted for lateral and circumferential movement on the disk supporting the same, and wherein said brake shoes are interconnected by links which operate to force the brake shoes into contact with the braking member movable with the wheel when said brake shoes are turned relative to each other radially of the wheel through the friction grip of the movable brake shoe on the braking memer.

' These and other objects will in part be obvious and will in part be hereinafter more fully disclosed.

In the drawing- Figure 1 is a vertical sectional view through a portion of a vehicle wheel showing the improved braking means applied thereto;

I Fig. 2 is a view in section through the drum and showing the braking means in side elevation as .viewed from the outer side of the wheel;

Fig. 3 is a sectional view on the line 3-3 of Fig. 2, and

Fig. 4 is a sectional view on the line 44 of Fig. 3. J

The invention as illustrated is applied to the wheels of a motor vehicle, but it will be understood that it maybe used in other ways with motor vehicles and with other rotating members. Attached to the wheel is a drum carrying a braking 5 member which is mounted thereon so that it is shiftable axially of the wheel, but turns circumferentially with the drum. Associated with this braking member are two disks, one of which is fixed to the chassis so that it is immovable thereon, and the other of which is mounted so that it can shift laterally of the wheel, but is held from turning movement relative to the disk with which .it is associated. Connecting these disks is a corrugated metal strip'which is joined to the disks so as to close the space between the disks, thus 1 forming a chamber which maybe put under vacuum. Fixed to one of the disks is a brake shoe. Mounted on the other disk for circumferential movement thereon is a brake shoe, and this brake shoe has no lateral movement relative to i the disk on which it is mounted. Connecting the two brake shoes at intervals are links having pivoted heads, so that the links may swing in a circumferential direction. When the cham- 5 her is put under vacuum, the movable disk will carry its associated brake shoe into contact with the braking member'and force the braking member into contact with the brake shoe on the fixed disk. The frictional grip of the brake shoe mounted for circumferential movement will cause said brake shoe, through the swinging of the links, to be drawn into firm gripping contact with the braking member. A pipe leading from the chamber between the disks and connected to a vacuum creating means is connected thereto at a point adjacent the upper ends of the disks. The chamber between the disks is filled with a liquid to a point a slight distance below the pipe so that when the movable disk shifts and reduces the space containing the liquid, it will not be caused to overflow into the suction pipe. This liquid reduces the space which must be put under vacuum, and very greatly decreases the time necessary for applying the brake shoes to the braking member.

Referring more in detail to the drawing, the invention is shown as applied to a motor vehicle wheel of the disk type, and the body of the wheel is indicated at I. The outer hub is indicated at if and the axle housing is indicated at 3. At-

tached to the wheel is a brake drum 4 having an' overhanging flange 5. These features are all of the usual construction and further description thereof is not thought necessary.

Attached to the axle housing 3 is a disk 6. Said disk is secured to' the housing by suitable bolts 1, I. This fixes the disk 6 so that it is stationary with the axle housing, and has no lateral movement relative to the wheel or circumferential movement relative to the axis of the wheel. Associated with the disk 6 is a disk 8 having an opening therethrough adapted to receive the hub 9 of the disk 6. A flexible member l0 joins the disk 8 to the hub 9. Said flexible member I0 is secured to the hub 9 by a plate II and is se- 9 i9, is, however, free to move in a circumferential cured to the disk 8 bya clamping ring l2. This ,disk 8 can move laterally relative to the disk 6,

but it hasno circumferential movement relative to the disk 6. Said disk 8 may be keyed to the hub 9 or otherwise restrained from radial movement relative to the disk 6.

Attached to the flange 5 of the brake drum is a braking member l3 which maybe of any suitable material. Said braking member is provided with inclined braking surfaces It and I5. This braking member is attached to the drum so that it turns with the drum, but it also has a lateral movement on the drum. This is accomplished by suitable interengaging lugs and recesses formed onthe drum and thebraking member.

Attached to the disk 6 is a brake shoe I6. The

brake shoe I 6 is fixed to the disk by clamping bolts II. This brake shoe is provided with an inclined braking face l8 which is adapted to make contact with the braking face It on the braking member l3. Carried by the disk 8 is a brake shoe l9 -having a braking face which is adapted to make contact with the braking surface l5 on the braking member l3. 'The brake shoe I9 is in radial alinement with the disk 8 and is supported thereon by a plate 2| which overlies the brake shoe at its peripheral edge. This plate 21| terminates adjacent a shoulder 22 on the brake shoe l9 and the brake shoe while supported on the disk and the plate is free to turn circumferentially on these supporting members.

' ment of the disk 8 to the left, as viewed in Fig.

1, will, however, force the brake shoe 1!! into contact with the braking member l3.

Connecting the outer ends of the disks 6 and I, is a corrugated sheet metal member 23 which is preferably. formed of copper and is analogous to a sylphon bellows. This member extends all the way around the disks, and closes the space.

between the ,disks at the outer side thereof, thus forming a chamber 24 which can be placed under vacuum. .The metal member 23 is secured in any suitable way to the disks in order to provide a tight joint therebetween. Attached to the disk 6 is a pipe 25 which leads to a vacuum creating means. Said pipe is preferably joined to a suitwheel.

able header and the header to the intake manifold through a control valve mechanism so that the degree or vacuum on the chamber 24 maybe varied for thus creating a diiferential pressure on oppositesides of the disk I, which is variable 24 is placed under vacuum, then the disk 8 will be moved toward the disk 6, and this will cause.

the brake shoe I! to contact with the brakin -member l3 andtoforcesaidbrakingmember |3 into contact with the brake shoe IS, and in this manner, the. braking member is gripped and retarded, thus stopping the rotation of the vehich Located between the disk and the'brake shoe It is a-sheet of asbestos-indicated at 26. like wise, between the plate II-,and-the disk 8 is a Any lateral move- When the chamber mustbecreatedis .jareaordiflerentialpresuremovingthediskl sheet of asbestostL'Thepurpweof bestos is to prevent'heat transfer from t e brake shoes to the disks. This heat insulation etween the brake shoes and the disks forms no part of the present invention, but'is shown, described and claimed in my co-pending' application Serial No.

Fixed to the brake shoe 16 are a series of pins 28. These pins extend through slots 29 in the brake shoe l9 and are provided with heads which limit the outward movement of the brake shoe l9v relative to the brake shoe IS. The brake shoe directionthrough a limited range on these pins. Attached to the brake shoe J6 are a series of links 30. Each link is provided with laterally projecting cylindrical members 3|, 3|, and these cylindrical members 3|, 3| rest in suitable recesses formed in the brake shoe l6. There is a recess 32 in the brake shoe l6 which permits the link to swing from thefull line position, shown in Fig. 3, to the broken line-position. Each link extends through the brake shoe |9. Attached to the end of the link is a head 33 which is likewise provided with lugs which, at their inner faces, are circular in cross section. These lugs bear in similar shaped recesses in the brake shoe l9 and are shaped so that the head may swing from the full line position, shown in Fig. 3, to the broken line position shown therein. A nut 34 is threaded on to the end of each link and serves as an abutment for the head 33. There is a recess 35 in this brake shoe H which permits the brake shoe l9 to move in acircumferential direction relative to the brake shoe I6. when the brake shoe l9 moves in this circumferential direction, so as to bring the links to the inclined position indicated in the broken lines in Fig. 3, they will force the brake shoe Is to move toward the brake shoe l6. Likewise, when the brake shoe I8 is moved circumferentially in the opposite direction, then it will move away from the brake shoe l6.

In the operation of my improved braking mechanism, the chamber 24 is placed under vacuum suilicient to create a difl'erential pressure that will force the disk 0 laterally-toward the disk 6, and this will'cause the brake shoe I! to contact with the braking member l3 and force the braking member l3 intocontact with the brake shoe l6. As soon as the brake shoe l9 contacts with the braking member II, the frictional grip therebetween will cause said brakeshoel! toturn in a circumferential direction on the disk 8, and this will swing thelinks 3. to the broken'line position shown in Fig. 3, which will in'turn force the brake shoe I! intoaflrmergrip withthe braking member I3, and the braking member |3 into firmer grip with the brake shoe l6. The vacuum chamber 24 is filled with a liquid indicated at It. -Theleveloftheliquidinthevacumnchamber,

when the disks are fully separated is indicated.

at 31 in Fig. 1. when the disks are moved into contact with the braking member, then the vacuum chamberisdecreasedinsizaandthiswill raise the level of the liquid 36 and change its J form without altering its volume, but not sufllciently to cause it to-flow into the suction pipe 25.

Whenitisdesircdtoapplythebrakeatheoniy.

space from which air must be drawn and on which .avacuumiscreated,isthespaceabovetheliquid in the vacuum chamber Y 24, and therefore a vac-' .uum'mav be'drawn very quickly onthis space.

Whilethesiaeofthechamberonwhichavacuum' uced to a minimum,'the

chamber 24 to the hub member carried by the disk 8. In otherwords, whatever may be the pressure on the surface ofthe liquid relative to atmospheric pressure, this is transmitted through the liquid to every point where the liquid contacts with the disk 8. It is often extremely important in a motor vehicle to apply the brakes quickly,

and this can be accomplished by the braking means described above, due tothe fact that the 4 volume of air necessary to be withdrawn from the brake shoe i9 is moved suiliciently to bring about a frictional grip through its contact with the braking member I 3, it will then 'move with the braking member l3 to a limited extent, swing ing the links 30 and thus very quickly bringing into action the maximum brakingpressure on the braking member which can be accomplished at the set degree of vacuum pull on the vacuum chamber. Not only will the braking members be .quickly brought into contact with the braking to add to surface, but the toggles will operate at all times the pressure on thebraking member in direct and in fixed proportion to the degree of vacuum on the chamber. When the degree of vacuum on the chamber 24 is increased or brought back to atmospheric pressure, then the metal plate 23 expanding will separate the disks and geleaisae the braking pressure on the braking mem- It is obvious that minor changes in the details of construction and the arrangement of the parts may be made without departing from the spirit of the invention-as set forth in the appended claims.

Having thus described. the invention, what I claim as new and desire to secure by Letters Patent, is-

'1. In a braking mechanism for motor vehicles, the combination of a braking member secured to and rotatable with a vehicle wheel, spaced nonrotating disks having movement relative to each other, a brake shoe associated with each disk and adapted to grip therebetween said-braking memher when the disks ber when the disks are moved toward each other, means connecting said disks and forming therebetween a vacuum chamber, and a pipe connection through one of said disks with said chamber ber having a liquid therein, the level of which, wghen' the brakes are applied, is slightly below said P 1 2. In a braking mechanism for motorvehicles, the combination of a braking member secured to and rotatable with a vehicle wheel, spaced nonrotating disks having movement relative to each other, a brake shoe associated with each disk and adapted to grip therebetween said braking memare moved toward each other, flexible members connecting said disks and forming therebetween a vacuum chamber, said flexible members including a flexible metal member join ing the outer edges of being constructed so as to yieldingly separate ber when the disks are moved said disks, said member said disks, and a pipe connection through one of said, disks with the said chamber adiacentthe upper end thereof whereby said chamber may be placed under vacuum,- said chamber having a liquid therein, the level of which, when the brakes are applied, is slightly below said pipe.

3.' In a braking mechanism for motor vehicles, the combination of a braking member secured to and rotatable with a vehicle wheel, spaced non-' rotating disks having movement relative to each other, a brake shoe associated with each disk and adapted to grip therebetween said braking member when the disks are moved toward each other,

Vmeans connecting said disks and forming there between a vacuum chamber, a pipe connection through one of said 'disks with said chamber whereby said chamber may be placed under vacuum, one of said brake shoes being fixed to its associated disk and the other brake shoe being supported on its associated disk for circumferential movement, and links connecting said brake shoes and operating to move said brake shoes toward each other through the frictional drag of said movable brake shoe on said braking member.

4. In a braking mechanism for motor vehicles, the combination of a braking member secured to and rotatable with a vehicle wheel, spaced non- 'rotating disks having movement relative to each other, a brake shoe associated with each disk and adapted to grip therebetween said braking member. when the disks are moved toward each other, means connecting said disks and forming therebetween a vacuum chamber, apipe connection through one of saiddisks with said chamber whereby said chamber may be placed under vacuum, one of said brake shoes being fixed to its associated disk and the other brake shoe being supported on its' associated disk so as to move circumferentially thereon, pins carried by one of said disks and extending through slots in the other disk, a plate carried by the disk supporting the movable brake shoe and overlying the same i for forcing said brake shoe into contact with the movable member when the chamber is placed under vacuum, and means connecting said brake shoes whereby the circumferential movement of one brake shoe will force said brake shoes toward each other when said brake shoes contact with said braking member.

5. In a braking mechanism for motor vehicles, the combination of abraking member secured to and rotatable with a vehicle wheel, spaced nonrotating disks having movement relative to each other, a brake shoe associated with each disk and adapted to grip therebetween said braking memtoward each other, flexible members connecting said disks and forming therebetween a vacuum chamber, said flexible members including a flexible metal member Joining the outer edges of said disks, said member being constructed so as to yieldingly separate said disks, and a pipe connection through one of said disks with said chamber whereby said cham- 7 vacuum.

6. Ida braking mechanism for motor vehicles, the combination of a braking member secured to and rotatable with a vehicle wheel, spaced nonsaid disks with said chamber whereby said chamber may be placed under vacuum, one of said brake shoes being fixed to the disk with which it is associated and the other brake shoe having a circumferential movement relative to its associated disk, a plate carried by said last-named disk and overlying said movable brake shoe for forcing the same into contact with the braking member when the chamber is placed under vacuum, and links connecting said brake shoes, said links being pivotally connected to each brake shoe and arranged so that when said movable brake shoe contacts with the braking member and turns therewith, said links will draw said brake shoes into intimate contact with said braking member.

7. In a braking mechanism for motor vehicles, the combination of a braking member secured to and rotatable with the vehicle wheels, spaced non-rotating disks having movement relative to each other, a brake shoe associated with each disk and adapted to grip'therebetween said braking member when one disk is moved toward the other, means connecting said disks and forming therebetween a vacuum chamber, a pipe conneci j tion through one of said disks with said chamber adjacent the upper end thereof whereby said chamber may be placed under vacuum, said chamber having a moldable mass therein, the

level of which when the brakes are applied is slightly below saidpipeand which by movement of one of said plates or disks relative. to the other may change its form without changing its volume.

8. In a braking mechanism for motor vehicles,

the combination of a braking member secured to and rotatable with a vehicle wheel, spaced nonrotating disks having movement relative to each other, a brake shoe rigidly attached to each disk and adapted to grip therebetween said braking member when the disks are moved toward each other, means connecting said disks and forming therebetween a chamber, a pipe connected to said chamber and adapted to be connected with a vacuum creating means, said chamber having a liquid therein contacting with said non-rotating disks and on which liquid a pressure less than atmosphericpressure may be-imposed by said vacuum creating means for causing said'disks to move toward each other for gripping the brake shoe.

FREDERICK L. SHELOR. 

